490 likes | 1.18k Views
Biochar Properties & Production Techniques. Zoe Wallage Low Carbon Innovation Centre University of East Anglia. Presentation Outline. Introduction & Overview Biochar Production Techniques Biochar Properties & Uses UEA Case Study Summary of Findings. UEA’s Biomass Gasification CHP Plant.
E N D
Biochar Properties & Production Techniques Zoe WallageLow Carbon Innovation CentreUniversity of East Anglia
Presentation Outline • Introduction & Overview • Biochar Production Techniques • Biochar Properties & Uses • UEA Case Study • Summary of Findings UEA’s Biomass Gasification CHP Plant
Atmospheric Carbon(CO2) Terrestrial Carbon(SOC) Research Overview • Aim: • Review the potential for carbon sequestration via biochar & assess the impact this technology may have on regional productivity & sustainability • Objectives: • Evaluate the technologies available for biochar production • Identify the parameters influential to biochar yield & quality
Lehmann (2007) Nature 447: 143 - 144 Biochar Carbon Cycle Lehmann et al (2006)Mitigation & Adaptation Strategies for Global Change 11: 403 - 427
Thermal Conversionof Biomass Lehmann (2007) Frontiers in Ecology & the Environment 5: 381 - 387
Syn Gas Heat without Air Bio Oil Biomass Biochar Thermal Conversion of Biomass • Overall an endothermic process: • Energy is required to initiate the process • At present the technologies can be split into two distinct categories: • Charcoal production • Bio oil or syn gas production • However, there is potential to move towards a third: • “Tri-generation” that makes use of the biochar, energy-rich co-products (bio oil, syn gas) & heat
Biochar ProductionTechniques CHP Gasification Slow Pyrolysis (retort) Slow pyrolysis (kiln) Fast Pyrolysis
Biochar Production Dynomotive: Bio oil via Fast Pyrolysis Eprida: Hydrogen & Char Fertiliser via Pyrolysis University of Hawaii: Flash Carboniser (Fast Pyrolysis) BEST Energies: Biochar via Slow Pyrolysis
Biochar Properties • High carbon content (60 – 95% C) • Resistant to biodegradation • Significant adsorptive qualities (similar to activated carbon) • Nutrients (& contaminants) essentially lock on to the structure • Increases moisture holding capacity • Enhances microbial biomass
Biochar Properties:Process Conditions • Enhanced biochar yields from: • Lower temperatures (<400C) • Higher pressures • Longer vapour residence time • Slower heating rate • Larger particle size
As temperature increases: Biochar yield decreases Fixed carbon increases Surface area increases Ash content increases Temperature Structural Development Biochar Properties:Process Conditions
Biochar Properties:Feedstock Materials • The variable nature of the chemical constituents in the feedstock biomass influence the structure, properties & yield of biochar. Roundwood Woodchip Rice Husks
Biochar Properties:Feedstock Materials Poultry Litter Manure Biodegradable Waste Softwood Hardwood
Gasification Outputs Biochar
Biochar UEA Case Study 1.4 MWe 2.0 MWth 6, 719 t CO2 yr-1 (34%↓) 3% Biochar Yield 300 t char yr-1 195 t C yr-1 716 t CO2 yr-1 (4% ↓) ...& this particular system is optimisedfor energyproduction!
Syn Gas Heat without Air Bio Oil Biomass Biochar Summary of Findings • Biochar is produced by the thermal decomposition of biomass using: • Slow Pyrolysis • Fast Pyrolysis • Gasification • Technology must be “closed-loop” with efficient product recovery • Biochar yield & quality varies significantly with feedstock type & process conditions • Biomass gasification CHP is currently viable & will produce modest quantities in the near-term
So, the future is in our hands… Thank you! Zoe.Wallage@uea.ac.uk 01603 591279